Problem: Christopher drove his car for $5$ miles on each of the past $4$ days. How many miles did Christopher drive his car altogether?
Explanation: The total number of miles driven is the product of the number of miles driven each day and the number of days that Christopher went driving. The product is $5\text{ miles per day} \times 4\text{ days}$ $5\text{ miles per day} \times 4\text{ days}= 20\text{ miles}$ Christopher driven a total of $20$ miles.